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4A30.30 - Forces Produced by Thermal Contraction

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​4A30.30 - Forces Produced by Thermal Contraction

Preview
SelectSelected
Title4A30.30 - Forces Produced by Thermal Contraction
Objective

Demonstrate the forces produced by thermal contraction.

StatusAvailable
Assembly Instructions

Overview
Use a blast shield to prevent broken rod pieces from flying into audience.

Instructions
A cast iron pin is inserted in the hole at the end of the center bar and the center bar is then heated by putting it on a ring stand over a fan shaped burner. After the bar is very hot, tighten the screw down against the frame, thus taking up the slack produced by the expansion. Now leave the bar to cool, or cool it with some water, and the pin will break with a snap.


Setup Time10
Operation Time
Preview Time5
Operation Instructions

​Put on heat gloves. Heat steel bar with propane torch.  Tighten screw until cast iron pin is firmly against the frame, taking up slack of expansion of rod.  Be sure not to tighten too tight or you can manually break the pin.  Either turn on fan or cool with water or let bar cool.  When bar contracts, forces pin to snap due to the amount of the force produced by the contraction of the steel rod.

ExportableNo
Demo on DimeNo
PIRA 200No
Export Instructions (if different)
HazardsNone
Analysis/Information
Category4 Thermodynamics
Subcategory4A - Thermal Properties of Matter
Keywordssolid expansion, tyndall, bar breaker, tyndalls
Construction Information
 
  
  
thermal contraction apparatus
1
cast iron pin
1
meker burner
1
ring stand
1
lighter
1
heat gloves
2
danger sign
1